FIG. 7.

LacZ expression from wild-type and mutant regulatory regions of the sol operon in vivo. Growth (•), butanol formation (dotted line), and β-galactosidase activity were assayed during the bacterial growth cycle for strains carrying the plasmids shown in Fig. 6. Symbols: □, wild type (pZF-sol); ◊, pZF-sol-R1; +, pZF-sol-R2; ×, pZF-sol-R3; ○, pZF-solR1/R2; ∗, pZF-sol-spo0A; ▵, pZF-sol-act. Growth and butanol formation patterns were virtually identical in all experiments. For the sake of clarity, only the data obtained with pZF-solR1/R2 are shown.